[processing][gdal] More nodata handling fixes

Fixes #18748

Author: nyalldawson

python/plugins/processing/algs/gdal/gdal2tiles.py

@@ -189,8 +189,8 @@ def getConsoleCommands(self, parameters, context, feedback, executing=True):
             arguments.append('-s')
             arguments.append(crs.authid())
 
-        nodata = self.parameterAsDouble(parameters, self.NODATA, context)
-        if nodata:
+        if self.NODATA in parameters and parameters[self.NODATA] is not None:
+            nodata = self.parameterAsDouble(parameters, self.NODATA, context)
             arguments.append('-a')
             arguments.append(str(nodata))
 

python/plugins/processing/algs/gdal/proximity.py

@@ -138,7 +138,10 @@ def getConsoleCommands(self, parameters, context, feedback, executing=True):
         inLayer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
         distance = self.parameterAsDouble(parameters, self.MAX_DISTANCE, context)
         replaceValue = self.parameterAsDouble(parameters, self.REPLACE, context)
-        nodata = self.parameterAsDouble(parameters, self.NODATA, context)
+        if self.NODATA in parameters and parameters[self.NODATA] is not None:
+            nodata = self.parameterAsDouble(parameters, self.NODATA, context)
+        else:
+            nodata = None
         options = self.parameterAsString(parameters, self.OPTIONS, context)
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
 
@@ -158,7 +161,7 @@ def getConsoleCommands(self, parameters, context, feedback, executing=True):
             arguments.append('-maxdist')
             arguments.append(str(distance))
 
-        if nodata:
+        if nodata is not None:
             arguments.append('-nodata')
             arguments.append(str(nodata))
 

python/plugins/processing/algs/gdal/rasterize.py

@@ -192,8 +192,8 @@ def getConsoleCommands(self, parameters, context, feedback, executing=True):
         if self.parameterAsBool(parameters, self.ALL_TOUCH, context):
             arguments.append('-at')
 
-        nodata = self.parameterAsDouble(parameters, self.NODATA, context)
-        if nodata:
+        if self.NODATA in parameters and parameters[self.NODATA] is not None:
+            nodata = self.parameterAsDouble(parameters, self.NODATA, context)
             arguments.append('-a_nodata')
             arguments.append(nodata)
 

python/plugins/processing/algs/gdal/warp.py

@@ -166,7 +166,10 @@ def getConsoleCommands(self, parameters, context, feedback, executing=True):
         out = self.parameterAsOutputLayer(parameters, self.OUTPUT, context)
         sourceCrs = self.parameterAsCrs(parameters, self.SOURCE_CRS, context)
         targetCrs = self.parameterAsCrs(parameters, self.TARGET_CRS, context)
-        nodata = self.parameterAsDouble(parameters, self.NODATA, context)
+        if self.NODATA in parameters and parameters[self.NODATA] is not None:
+            nodata = self.parameterAsDouble(parameters, self.NODATA, context)
+        else:
+            nodata = None
         resolution = self.parameterAsDouble(parameters, self.TARGET_RESOLUTION, context)
 
         arguments = []
@@ -178,7 +181,7 @@ def getConsoleCommands(self, parameters, context, feedback, executing=True):
             arguments.append('-t_srs')
             arguments.append(targetCrs.authid())
 
-        if nodata:
+        if nodata is not None:
             arguments.append('-dstnodata')
             arguments.append(str(nodata))